Laundry dryer comprising a lint filter

ABSTRACT

The present invention relates to a laundry dryer ( 1 ) comprising a body ( 2 ), an air duct ( 3 ) that is arranged on the body ( 2 ) and wherein the circulation of processing air (PA) that enables the laundry to be dried is performed and a lint filter ( 4 ) that is disposed inside the air duct ( 3 ) and where the lints that break off the laundry are collected.

The present invention relates to a laundry dryer comprising a lint filter.

In laundry drying machines, the lints etc. that break off from the laundry mix into the processing air of the machine. The lints that break off may accumulate on components like the propeller or the fan due to the air flow. In conventional machines, in order to solve this problem, lint filters are used on the processing air duct and the lints that break off from the laundry during the drying process and mix into the processing air are accumulated on the filter. The lint filters can be clogged in the course of time and cause the drying performance to decrease and energy consumption to increase. The filters that are not cleaned timely result in loss of energy by decreasing the drying performance.

In the European Patent Application No. EP0106289, a laundry dryer is disclosed, that monitors the clogging degree of the lint filter by using the effect of electrical conductivity.

In the U.S. Pat. No. 7,926,201, a laundry dryer is disclosed, that detects the clogging degree of the lint filter.

In the Japanese Patent Application No JP3958523, a laundry dryer is disclosed, that detects the clogging degree of the lint filter by the differential pressure.

The aim of the present invention is the realization of a laundry dryer wherein the clogging degree of the lint filter can be measured effectively.

The laundry dryer realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a filter enabling the lints that break off from the laundry to be retained, at least two plates disposed on the filter, a capacitance detection unit measuring the capacitance value between the plates, and a control unit that calculates the clogging degree of the filter by analyzing the values received from the capacitance detection unit.

In an embodiment of the present invention, the user is alerted by means of an indicator if the lint filter is clogged and not cleaned at the start of the drying process and the control unit delays the drying process until the lint filter is cleaned. Thus, the users who forget to clean the lint filter are alerted at the start of the drying process and are enabled to clean the lint filter.

In an embodiment of the present invention, the user is alerted audibly and/or visually to clean the filter if the lint filter is clogged during the drying process and needs to be cleaned. Thus, the drying process is continued without the drying performance decreasing by cleaning the lint filter during the drying process.

In an embodiment of the present invention, there is provided an indicator, having audible and/or visual alerter, that becomes active in situations when the filter is clogged and needs to be cleaned. For example, a light on the indicator is turned on when the filter is clogged and the user understands the filter has to be cleaned upon seeing the light. Thus, the user does not have to control and clean the filter at the end of each drying process.

In an embodiment of the present invention, there is a light source on the indicator, the brightness of which changes depending on the amount of lint collected on the lint filter. The light source becomes less bright when the filter is slightly clogged and brightness increases as the filter clogging degree increases. Thus, the user is informed about the amount of lint collected on the filter without dislodging the filter.

In an embodiment of the present invention, an indicator is provided that is composed of at least two light sources. The number of light sources becoming active increases depending on the clogging degree of the filter. Thus, the user can monitor the clogging degree of the filter immediately.

In an embodiment of the present invention, a V-shaped filter having two panels facing each other is used. In this embodiment, the plates connected to the capacitance detection unit, are placed so as to face each other and each one is disposed on one panel. Thus, the present invention can be used independently of the lint filter type.

In an embodiment of the present invention, there is provided a connection means that is disposed on the filter, which provides the electrical connection between the plates and the capacitance detection unit, and a housing disposed on the air duct wherein the connection means is seated. By means of the connection means and the housing, the electrical connection is provided between the capacitance detection unit and the plates on the filter which can be attached to/dismounted from the laundry dryer for cleaning.

In an embodiment of the present invention, if the lint filter is not mounted to the laundry dryer, the capacitance detection unit detects that the lint filter is not mounted by measuring the capacitance. In this embodiment, whether or not the filter is mounted can be determined without using an additional sensor. When the lint filter is determined not to be mounted, the control unit gives the filter not in place warning by means of the indicators.

In the laundry dryer of the present invention, the difference in dielectric coefficient between air and lint is utilized by placing plates on the filter in order to measure the filling rate of the lint filter. Furthermore, the clogging degree of the lint filter can be measured effectively by means of the capacitance detection unit, the control unit and the indicators, the user can monitor the state of the filter immediately. The user is enabled to clean the lint filter only when required and thus both energy is saved and the work load of the user is decreased.

The laundry dryer realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

FIG. 1—is the sideways schematic view of a laundry dryer.

FIG. 2—is the front schematic view of a laundry dryer.

FIG. 3—is the schematic view of a V-shaped lint filter in an embodiment of the present invention.

The elements illustrated in the figures are numbered as follows:

1. Laundry dryer

2. Body

3. Air duct

4. Lint filter

5. Panel

6. Plate

7. Capacitance detection unit

8. Control unit

9. Indicator

10. Housing

11. Connection means

The laundry dryer (1) comprises a body (2), an air duct (3) that is arranged on the body (2) wherein the circulation of processing air (PA) that enables the laundry to be dried is performed and a lint filter (4) that is disposed inside the air duct (3) and that separates the lints in the processing air (PA).

The laundry dryer (1) of the present invention comprises at least two electrically conductive plates (6) disposed oppositely on the filter (4) and a capacitance detection unit (7) that is connected electrically to the plates (6) and that measures the capacitance value formed between the plates (6), and a control unit (8) that detects the amount of lint collected in the lint filter (4) depending on the data received from the capacitance detection unit (7) (FIG. 1, FIG. 3).

The capacitance value between the plates (6) changes depending on the amount of lint collected on the lint filter (4). The dielectric coefficient of the lints collected on the lint filter (4) is greater than the dielectric coefficient of air and hence the capacitance value between the plates (6) increases as lints are accumulated on the lint filter (4). The capacitance detection unit (7) measures the capacitance value formed between the plates (6) by applying high frequency alternative current to the plates (6) and transmits the value to the control unit (8). The control unit (8) decides whether or not the filter (4) is clogged and whether it needs to be cleaned with respect to the measured capacitance value.

In an embodiment of the present invention, the laundry dryer (1) comprises indicators (9) disposed on the body (2). If the measured capacitance value is above a threshold capacitance value (Cesik) predetermined by the manufacturer, the control unit (8) decides that the filter (4) is clogged to the degree of affecting the drying performance and the user is alerted audibly and/or visually by means of the indicators (9) that the filter (4) is required to be cleaned (FIG. 1, FIG. 2).

In a derivative of this embodiment, the brightness rate of the light sources on the indicator (9) changes depending on the amount of lint accumulated on the lint filter (4). The brightness of the light sources increases as the amount of lints accumulated on the lint filter (4) increases. Consequently, the user can monitor the amount of lint collected through the indicator (9) (FIG. 1, FIG. 2).

In another derivative of this embodiment, the indicator (9) is composed of at least two light sources. The number of light sources becoming active increases depending on the clogging degree of the filter (4). For example, in the indicator (9) composed of five LEDs, the clogging degree of the filter (4) is shown by dividing into five units, if two of the five LEDs are emitting light, it means that the filter (4) is roughly 40% clogged.

In an embodiment of the present invention, the control unit (8) controls the clogging degree of the lint filter (4) by means of the capacitance detection unit (7) at the start of the drying process. If the measured capacitance value is above a threshold capacitance value (Cesik), the control unit (8) does not start the drying process and the user is alerted that the lint filter (4) needs to be cleaned by means of the indicator (9). The control unit (8) starts the drying process after the lint filter (4) is cleaned.

In an embodiment of the present invention, if the lint filter (4) is clogged during the drying process, the control unit (8) enables the user to be alerted audibly and/or visually by means of the indicators (9). Thus, the lint filter (4) can be cleaned during the drying process and the drying process can be continued without the drying performance decreasing.

In an embodiment of the present invention, the filter (4) comprises two panels (5) that retain the lints and which are positioned to face each other in a V shape. The plates (6) are placed on the inner surfaces of the panels (5) so as to face each other oppositely.(FIG. 3).

In an embodiment of the present invention, a detachable lint filter (4) is used. The laundry dryer (1) comprises a connection means (11) that is disposed on the detachable lint filter (4) and that provides the electrical connection of the plates (6) with the capacitance detection unit (7) and a housing (10) arranged on the air duct (3), wherein the connection means (11) is seated. The connection means (11) are connected to the capacitance detection unit (7) by means of the housing (10) arranged on the air duct (3) (FIG. 1, FIG. 2, FIG. 3).

If the lint filter (4) is not mounted to the laundry dryer (1), the capacitance between the electrodes located on the housing (10) is measured when the capacitance detection unit (7) tries to measure the capacitance between the plates (6), and since the distance between the electrodes is longer than the distance between the plates (6), the measured capacitance value is much smaller than the capacitance value between the plates (6). In this situation, the control unit (8) enables the user to be alerted by means of the indicators (9).

In the laundry dryer (1) of the present invention, the clogging rate of the lint filter (4) is detected effectively by means of a low cost capacitance detection unit (7) and the plates (6) disposed on the lint filter (4), similar to working principles of state of the art parallel plate capacitors. The user can control the clogging degree of the lint filter (4) continuously by means of the indicators (9) controlled by the control unit (8). The user is enabled to clean the lint filter (4) only when required by means of the control unit (8) and thus both energy is saved and also the work load of the user is decreased. 

1. A laundry dryer (1) comprising a body (2), an air duct (3) that is arranged on the body (2) and wherein the circulation of processing air (PA) that enables the laundry to be dried is performed and a lint filter (4) that is disposed inside the air duct (3) and that filters the lints in the processing air (PA), characterized by at least two electrically conductive plates (6) disposed oppositely on the filter (4), a capacitance detection unit (7) that is connected electrically to the plates (6) and that measures the capacitance value formed between the plates (6) and a control unit (8) that detects the amount of lint collected in the lint filter (4) depending on the data received from the capacitance detection unit (7).
 2. A laundry dryer (1) as in claim 1, characterized by the control unit (8) deciding that the filter (4) is clogged if the capacitance value measured by the capacitance detection unit (7) is above a threshold capacitance value (Cesik) predetermined by the manufacturer.
 3. A laundry dryer (1) as in claim 1, characterized by the control unit (8) that does not start a new drying process until the lint filter (4) is cleaned when the lint filter (4) is clogged.
 4. A laundry dryer (1) as in claim 1, characterized by the control unit (8) that enables the user to clean the filter (4) by interrupting the process when the lint filter (4) is clogged during the drying process.
 5. A laundry dryer (1) as in claim 1, characterized by an indicator (9) that is disposed on the body (2) and that alerts the user audibly and/or visually when the lint filter (4) is clogged.
 6. A laundry dryer (1) as in claim 5, characterized by the indicators (9) comprising light sources, the brightness degrees of which continuously or gradually increase/decrease depending on the amount of lint accumulated on the lint filter (4).
 7. A laundry dryer (1) as in claim 1, characterized by the lint filter (4) having two panels (5) that hold the lints and that are positioned to face each other in a V shape and at least two electrically conductive plates (6) disposed oppositely on the inner surfaces of the panels (5).
 8. A laundry dryer (1) as in claim 1, characterized by a connection means (11) that is disposed on the detachable lint filter (4) and that provides the electrical connection of the plates (6) with the capacitance detection unit (7) and a housing (10) that is arranged on the air duct (3), wherein the connection means (11) is seated.
 9. A laundry dryer (1) as in claim 8, characterized by the control unit (8) that determines whether or not the lint filter (4) is in place by detecting whether or not the connection means (11) is mounted into the housing (10).
 10. A laundry dryer (1) as in claim 2, characterized by the control unit (8) that does not start a new drying process until the lint filter (4) is cleaned when the lint filter (4) is clogged.
 11. A laundry dryer (1) as in claim 2, characterized by the control unit (8) that enables the user to clean the filter (4) by interrupting the process when the lint filter (4) is clogged during the drying process.
 12. A laundry dryer (1) as in claim 2, characterized by an indicator (9) that is disposed on the body (2) and that alerts the user audibly and/or visually when the lint filter (4) is clogged.
 13. A laundry dryer (1) as in claim 12, characterized by the indicators (9) comprising light sources, the brightness degrees of which continuously or gradually increase/decrease depending on the amount of lint accumulated on the lint filter (4).
 14. A laundry dryer (1) as in claim 2, characterized by the lint filter (4) having two panels (5) that hold the lints and that are positioned to face each other in a V shape and at least two electrically conductive plates (6) disposed oppositely on the inner surfaces of the panels (5).
 15. A laundry dryer (1) as in claim 2, characterized by a connection means (11) that is disposed on the detachable lint filter (4) and that provides the electrical connection of the plates (6) with the capacitance detection unit (7) and a housing (10) that is arranged on the air duct (3), wherein the connection means (11) is seated.
 16. A laundry dryer (1) as in claim 15, characterized by the control unit (8) that determines whether or not the lint filter (4) is in place by detecting whether or not the connection means (11) is mounted into the housing (10). 